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Enter the number to validate

Spaces and line breaks are ignored automatically
Examples of testing.

Reference Table

TypeLengthChecksumAssigned byDo you want to change?
Steuernummer10-11 cifreNo standard checksumLocal Finance OfficeChange state
IdNr (Identifikationsnummer)11 cifreMOD-11 (variante Luhn)Bundeszentralamt fur SteuernPermanent
USt-IdNrDE + 9 cifreMOD-11Bundeszentralamt fur SteuernRarely

Come utilizzare Validatore Steuernummer e IdNr Germania

Attach your tax ID number or ID card

Validator accepts both formats. The tax ID has 10-11 digits with optional separators (/ or space). The ID number exactly has 11 digits.

Automatic Result

The system automatically detects the type (tax ID or ID number) and applies specific validation. For the ID number, a MOD-11 checksum is performed.

Interpret the result

View: numeric type, validation status, detailed message and contextual information about the number.

Suggerimenti

  • ID Number is required for many uses: ELSTER, Child Allowance, BAFOG, communication with tax authorities.
  • Tax number in the ELSTER format of 13 digits adds the Federal State code (first two digits) to the local tax number. This calculator only validates the local format.
  • Generate Test IDNR using format: first digit 1-9, no repetition in digits 2-10, valid MOD-11 checksum.
  • Tax ID number of a capital company (GmbH) differs from personal tax ID numbers of shareholders.

Domande frequenti

What is the difference between Steuer-Number and ID Number?

Tax ID number (10-11 digits) is assigned by the local Finanzamt and changes if changing Federal States. The Identification Number (11 digits) is assigned at birth by the Federal Central Office and never changes.

How is the tax number structured?

Depends on the state. Bayern: FF/BBB/UUUUP. North Rhine-Westphalia: FFF/BBBB/UUUUP. The format varies in 16 different regional schemes. The first 2-3 digits identify the Finanzamt.

How does the MOD-11 checksum of the ID Number work?

The algorithm MOD-11 processes the first 10 digits with a series of multiplications and additions modulo 11. The check digit (11th) is compared to the result. If they match, the ID number is valid.

Where is my tax ID number?

Tax Return Notice (tax assessment notice), on communications from the tax office, on sales tax return notification. The ID number is notified by mail from the Federal Central Office.